Relationship between napp and steady-state O2 uptake rate at Y = 50% (VY50). The VY50 values were obtained from the hyperbolic curves in Fig. 2. The symbols (mean ± SD) are as in Fig. 2. The solid line, which was calculated from the equation: napp = 1 + 1.23*VY50/(0.193 + VY50), simulates the observed dependence. The maximal value of napp at infinite VY50 is 2.23, which was obtained using the Hanes-Woolf plot, VY50/(napp - 1) vs. VY50. The inset figure shows the relationship between napp and O2 transport efficiency (EO2) (see Text).